is_void Class
Visual Studio 2015
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Tests whether the type is void.
template <class T> struct is_void;
Parameters
T
The type to query.
An instance of the type predicate holds true if the type T is void or a cv-qualified form of void, otherwise it holds false.
// std__type_traits__is_void.cpp // compile with: /EHsc #include <type_traits> #include <iostream> struct trivial { int val; }; int main() { std::cout << "is_void<trivial> == " << std::boolalpha << std::is_void<trivial>::value << std::endl; std::cout << "is_void<void()> == " << std::boolalpha << std::is_void<void()>::value << std::endl; std::cout << "is_void<void> == " << std::boolalpha << std::is_void<void>::value << std::endl; return (0); }
is_void<trivial> == false is_void<void()> == false is_void<void> == true
Header: <type_traits>
Namespace: std
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